1. Field of the Invention
The invention relates in general to a backlight module, and more particularly to a backlight module adopting an extruded metallic carrier with heat radiating function and high structural evenness as the bezel.
2. Description of the Related Art
Along with the rapid advancement in the manufacturing technology of liquid crystal display (LCD) as well as the advantages of compactness, slimness, energy saving and low radiation, LCD has been widely applied in a variety of electronic products such as personal digital assistant (PDA), notebook computer, digital still camera, digital video recorder, mobile phone, computer screen and liquid crystal TV. Further due to a huge input in research and development as well as the adoption of large-scale production facilities, the quality of LCD is continually improved while the cost is further cut down. The application of LCD is therefore expanding and thriving. Since the liquid crystal display panel used in an LCD is non-self-luminous, a backlight module is needed to provide necessary light for the display panel.
Referring to FIG. 1A, a partial sectional view of a conventional backlight module. In FIG. 1A, backlight module 10 includes a bezel 11, a reflector sheet 12, a light source such as plural cold cathode fluorescent lamps (CCFLs) 13 and a diffuser plate 14. Of which, an accommodation sink 11a is formed on the top-face of bezel 11; reflector sheet 12 is adhered onto the cell bottom 11b and two cell walls 11c of accommodation sink 11a. CCFLs 13 are lined up inside accommodation sink 11a with diffuser plate 14 being deposited at the top and reflector sheet 12 at the bottom.
Normally, bezel 11 is made of aluminum alloy via press molding of sheet metal. However, the cost of mold will increase as the size of backlight module 10 becomes larger. Furthermore, referring to FIG. 1B, a larger bezel 10 gets sunken easily, hence affecting the overall evenness greatly. In FIG. 1B, since bezel 11 fails to dissipate the heat generated by CCFLs 13, the luminance of backlight module 10 declines, meanwhile, diffuser plate 14 is likely to be deformed and caved in due to the heat accumulated inside bezel 11.